Camera Live-Vorschau friert auf Kamera wechseln
Ich erstelle eine benutzerdefinierte Kamera-App. Das Problem, dem ich gegenüberstehe, ist, dass die Kameravorschau einfriert, wenn ich zwischen der vorderen und der hinteren Kamera wechsle. Wenn Sie die Aktivität mit der vorderen oder hinteren Kamera starten, rufen Sie @ au
boolean opened = safeCameraOpenInView(view, Camera.CameraInfo.CAMERA_FACING_BACK)
ei der OnCreateView-Methode des Fragments werden beide Kameras beim Start wie erwartet angezeigt. Sobald ich die gleiche Methode im On-Click-Listener meines Switch-Buttons aufrufe, friert die Kamera sofort ein.
Dies ist eine neue Implementierung, die ich ausprobiert habe, bei der sich der gesamte Code innerhalb desselben Fragments befindet, anstatt einer benutzerdefinierten Klasse, die auf der folgenden Frage basiert:Custom Klasse Kamera Live-Vorschau friert auf Kameraschalter doch das ergebnis ist genau das gleiche. Ich bin mir ziemlich sicher, dass ich etwas mit der Oberflächenansicht tun muss, um sie an die neue Kamera zu binden, aber ich weiß nicht, wie ich das machen soll. Hat jemand ein paar Hinweise?
Meine Aktivität
public class Camera2ActivityFragment extends Fragment {
// Native camera.
private Camera mCamera;
// View to display the camera output.
private CameraPreview mPreview;
// Reference to the containing view.
private View mCameraView;
/**
* Default empty constructor.
*/
public Camera2ActivityFragment(){
super();
}
/**
* Static factory method
* @param sectionNumber
* @return
*/
public static Camera2ActivityFragment newInstance(int sectionNumber) {
Camera2ActivityFragment fragment = new Camera2ActivityFragment();
//Bundle args = new Bundle();
//args.putInt(ARG_SECTION_NUMBER, sectionNumber);
//fragment.setArguments(args);
return fragment;
}
/**
* OnCreateView fragment override
* @param inflater
* @param container
* @param savedInstanceState
* @return
*/
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_camera2, container, false);
boolean opened = safeCameraOpenInView(view, Camera.CameraInfo.CAMERA_FACING_BACK);
if(opened == false){
Log.d("CameraGuide","Error, Camera failed to open");
return view;
}
// Trap the capture button.
Button captureButton = (Button) view.findViewById(R.id.btnCameraStart);
captureButton.setOnClickListener(
new View.OnClickListener() {
@Override
public void onClick(View v) {
// get an image from the camera
mCamera.takePicture(null, null, mPicture);
}
}
);
Button switchCameraButton = (Button) view.findViewById(R.id.btnSwitchCamera);
switchCameraButton.setOnClickListener(
new View.OnClickListener() {
@Override
public void onClick(View v) {
safeCameraOpenInView(getView(), Camera.CameraInfo.CAMERA_FACING_FRONT); //ISSUE OCCURS HERE!
}
}
);
return view;
}
/**
* Recommended "safe" way to open the camera.
* @param view
* @return
*/
private boolean safeCameraOpenInView(View view, int camID) {
boolean qOpened = false;
releaseCameraAndPreview();
//mCamera = getCameraInstance(Camera.CameraInfo.CAMERA_FACING_BACK);
mCamera = getCameraInstance(camID);
mCameraView = view;
qOpened = (mCamera != null);
if(qOpened == true){
mPreview = new CameraPreview(getActivity().getBaseContext(), mCamera,view);
FrameLayout preview = (FrameLayout) view.findViewById(R.id.camera_view);
preview.addView(mPreview);
mPreview.startCameraPreview();
}
return qOpened;
}
/**
* Safe method for getting a camera instance.
* @return
*/
public static Camera getCameraInstance(int camID){
Camera c = null;
try {
c = Camera.open(camID); // attempt to get a Camera instance
}
catch (Exception e){
e.printStackTrace();
}
return c; // returns null if camera is unavailable
}
@Override
public void onPause() {
super.onPause();
}
@Override
public void onDestroy() {
super.onDestroy();
releaseCameraAndPreview();
}
/**
* Clear any existing preview / camera.
*/
private void releaseCameraAndPreview() {
if (mCamera != null) {
mCamera.stopPreview();
mCamera.release();
mCamera = null;
}
if(mPreview != null){
mPreview.destroyDrawingCache();
mPreview.mCamera = null;
}
}
/**
* Surface on which the camera projects it's capture results. This is derived both from Google's docs and the
* excellent StackOverflow answer provided below.
*
* Reference / Credit: https://stackoverflow.com/questions/7942378/android-camera-will-not-work-startpreview-fails
*/
class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {
// SurfaceHolder
private SurfaceHolder mHolder;
// Our Camera.
private Camera mCamera;
// Parent Context.
private Context mContext;
// Camera Sizing (For rotation, orientation changes)
private Camera.Size mPreviewSize;
// List of supported preview sizes
private List<Camera.Size> mSupportedPreviewSizes;
// Flash modes supported by this camera
private List<String> mSupportedFlashModes;
// View holding this camera.
private View mCameraView;
public CameraPreview(Context context, Camera camera, View cameraView) {
super(context);
// Capture the context
mCameraView = cameraView;
mContext = context;
setCamera(camera);
// Install a SurfaceHolder.Callback so we get notified when the
// underlying surface is created and destroyed.
mHolder = getHolder();
mHolder.addCallback(this);
mHolder.setKeepScreenOn(true);
// deprecated setting, but required on Android versions prior to 3.0
mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
}
/**
* Begin the preview of the camera input.
*/
public void startCameraPreview()
{
try{
mCamera.setPreviewDisplay(mHolder);
mCamera.startPreview();
}
catch(Exception e){
e.printStackTrace();
}
}
/**
* Extract supported preview and flash modes from the camera.
* @param camera
*/
private void setCamera(Camera camera)
{
// Source: https://stackoverflow.com/questions/7942378/android-camera-will-not-work-startpreview-fails
mCamera = camera;
mSupportedPreviewSizes = mCamera.getParameters().getSupportedPreviewSizes();
mSupportedFlashModes = mCamera.getParameters().getSupportedFlashModes();
// Set the camera to Auto Flash mode.
if (mSupportedFlashModes != null && mSupportedFlashModes.contains(Camera.Parameters.FLASH_MODE_AUTO)){
Camera.Parameters parameters = mCamera.getParameters();
parameters.setFlashMode(Camera.Parameters.FLASH_MODE_AUTO);
parameters.setRotation(90);
//parameters.setPreviewSize(mPreviewSize.width, mPreviewSize.height);
mCamera.setParameters(parameters);
mCamera.setDisplayOrientation(90);
}
requestLayout();
}
/**
* The Surface has been created, now tell the camera where to draw the preview.
* @param holder
*/
public void surfaceCreated(SurfaceHolder holder) {
try {
mCamera.setPreviewDisplay(holder);
//mCam = Camera.open();
//mCam.setPreviewDisplay(holder);
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* Dispose of the camera preview.
* @param holder
*/
public void surfaceDestroyed(SurfaceHolder holder) {
if (mCamera != null){
mCamera.stopPreview();
}
}
/**
* React to surface changed events
* @param holder
* @param format
* @param w
* @param h
*/
public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
//Log.e(TAG, "surfaceChanged => w=" + w + ", h=" + h);
// If your preview can change or rotate, take care of those events here.
// Make sure to stop the preview before resizing or reformatting it.
if (mHolder.getSurface() == null){
// preview surface does not exist
return;
}
// stop preview before making changes
try {
mCamera.stopPreview();
//mCamera.release();
} catch (Exception e){
// ignore: tried to stop a non-existent preview
}
// set preview size and make any resize, rotate or reformatting changes here
// start preview with new settings
try {
Camera.Parameters parameters = mCamera.getParameters();
parameters.setPreviewSize(mPreviewSize.width, mPreviewSize.height);
parameters.setRotation(90);
parameters.setFocusMode(Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE);
mCamera.setParameters(parameters);
mCamera.setDisplayOrientation(90);
mCamera.setPreviewDisplay(mHolder);
mCamera.enableShutterSound(true);
mCamera.startPreview();
} catch (Exception e){
//Log.d(TAG, "Error starting camera preview: " + e.getMessage());
}
}
/**
* Calculate the measurements of the layout
* @param widthMeasureSpec
* @param heightMeasureSpec
*/
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec)
{
/*
// Source: https://stackoverflow.com/questions/7942378/android-camera-will-not-work-startpreview-fails
final int width = resolveSize(getSuggestedMinimumWidth(), widthMeasureSpec);
final int height = resolveSize(getSuggestedMinimumHeight(), heightMeasureSpec);
setMeasuredDimension(width, height);
if (mSupportedPreviewSizes != null){
mPreviewSize = getOptimalPreviewSize(mSupportedPreviewSizes, width, height);
}
*/
final int width = resolveSize(getSuggestedMinimumWidth(), widthMeasureSpec);
final int height = resolveSize(getSuggestedMinimumHeight(), heightMeasureSpec);
if (mSupportedPreviewSizes != null) {
mPreviewSize = getOptimalPreviewSize(mSupportedPreviewSizes, width, height);
}
float ratio;
if(mPreviewSize.height >= mPreviewSize.width)
ratio = (float) mPreviewSize.height / (float) mPreviewSize.width;
else
ratio = (float) mPreviewSize.width / (float) mPreviewSize.height;
// One of these methods should be used, second method squishes preview slightly
setMeasuredDimension(width, (int) (width * ratio));
// setMeasuredDimension((int) (width * ratio), height);
}
/**
* Update the layout based on rotation and orientation changes.
* @param changed
* @param left
* @param top
* @param right
* @param bottom
*/
@Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom)
{
// Source: https://stackoverflow.com/questions/7942378/android-camera-will-not-work-startpreview-fails
if (changed) {
final int width = right - left;
final int height = bottom - top;
int previewWidth = width;
int previewHeight = height;
if (mPreviewSize != null){
Display display = ((WindowManager)mContext.getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
switch (display.getRotation())
{
case Surface.ROTATION_0:
previewWidth = mPreviewSize.height;
previewHeight = mPreviewSize.width;
mCamera.setDisplayOrientation(90);
break;
case Surface.ROTATION_90:
previewWidth = mPreviewSize.width;
previewHeight = mPreviewSize.height;
break;
case Surface.ROTATION_180:
previewWidth = mPreviewSize.height;
previewHeight = mPreviewSize.width;
break;
case Surface.ROTATION_270:
previewWidth = mPreviewSize.width;
previewHeight = mPreviewSize.height;
mCamera.setDisplayOrientation(180);
break;
}
}
final int scaledChildHeight = previewHeight * width / previewWidth;
mCameraView.layout(0, height - scaledChildHeight, width, height);
}
}
/**
*
* @param sizes
* @param width
* @param height
* @return
*/
private Camera.Size getOptimalPreviewSize(List<Camera.Size> sizes, int width, int height)
{
final double ASPECT_TOLERANCE = 0.1;
double targetRatio = (double) height / width;
if (sizes == null)
return null;
Camera.Size optimalSize = null;
double minDiff = Double.MAX_VALUE;
int targetHeight = height;
for (Camera.Size size : sizes) {
double ratio = (double) size.height / size.width;
if (Math.abs(ratio - targetRatio) > ASPECT_TOLERANCE)
continue;
if (Math.abs(size.height - targetHeight) < minDiff) {
optimalSize = size;
minDiff = Math.abs(size.height - targetHeight);
}
}
if (optimalSize == null) {
minDiff = Double.MAX_VALUE;
for (Camera.Size size : sizes) {
if (Math.abs(size.height - targetHeight) < minDiff) {
optimalSize = size;
minDiff = Math.abs(size.height - targetHeight);
}
}
}
return optimalSize;
}
}
/**
* Picture Callback for handling a picture capture and saving it out to a file.
*/
private Camera.PictureCallback mPicture = new Camera.PictureCallback() {
@Override
public void onPictureTaken(byte[] data, Camera camera) {
File pictureFile = getOutputMediaFile();
if (pictureFile == null){
Toast.makeText(getActivity(), "Image retrieval failed.", Toast.LENGTH_SHORT)
.show();
return;
}
try {
FileOutputStream fos = new FileOutputStream(pictureFile);
fos.write(data);
fos.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
};
/**
* Used to return the camera File output.
* @return
*/
private File getOutputMediaFile(){
File mediaStorageDir = new File(Environment.getExternalStoragePublicDirectory(
Environment.DIRECTORY_PICTURES), "Pocket Booth");
if (! mediaStorageDir.exists()){
if (! mediaStorageDir.mkdirs()){
Log.d("Camera Guide", "Required media storage does not exist");
return null;
}
}
// Create a media file name
String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
File mediaFile;
mediaFile = new File(mediaStorageDir.getPath() + File.separator +
"IMG_"+ timeStamp + ".jpg");
//DialogHelper.showDialog( "Success!","Your picture has been saved!",getActivity());
return mediaFile;
}
}